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排序方式: 共有9662条查询结果,搜索用时 46 毫秒
61.
Susanne Singer PhD Dorit Wollbrück MSc Andreas Dietz MD Juliane Schock MD Friedemann Pabst MD Hans‐Joachim Vogel MD Jens Oeken MD Annett Sandner MD Sven Koscielny MD Karl Hormes Kerstin Breitenstein MD Heike Richter Andreas Deckelmann Sarah Cook MSc Michael Fuchs MD Sylvia Meuret MD 《Head & neck》2013,35(11):1583-1590
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Verena Tenten Sylvia Menzel Uta Kunter Eva-Maria Sicking Claudia R. C. van Roeyen Silja K. Sanden Michaela Kaldenbach Peter Boor Astrid Fuss Sandra Uhlig Regina Lanzmich Brigith Willemsen Henry Dijkman Martin Grepl Klemens Wild Wilhelm Kriz Bart Smeets Jürgen Floege Marcus J. Moeller 《Journal of the American Society of Nephrology : JASN》2013,24(12):1966-1980
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The Prognostic Significance of Neutrophil‐to‐Lymphocyte and Platelet‐to‐Lymphocyte Ratios in Patients With Multiple Myeloma 下载免费PDF全文
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Circulating regulatory anti-T cell receptor antibodies in patients with myasthenia gravis 总被引:2,自引:0,他引:2 下载免费PDF全文
Jambou F Zhang W Menestrier M Klingel-Schmitt I Michel O Caillat-Zucman S Aissaoui A Landemarre L Berrih-Aknin S Cohen-Kaminsky S 《The Journal of clinical investigation》2003,112(2):265-274
Serum anti-T cell receptor (TCR) Ab's are involved in immune regulation directed against pathogenic T cells in experimental models of autoimmune diseases. Our identification of a dominant T cell population expressing the Vbeta5.1 TCR gene (TCRBV5-1), which is responsible for the production of pathogenic anti-acetylcholine receptor (AChR) autoantibodies in HLA-DR3 patients with early-onset myasthenia gravis (EOMG), prompted us to explore the occurrence, reactivity, and regulatory role of anti-TCR Ab's in EOMG patients and disease controls with clearly defined other autoantibodies. In the absence of prior vaccination against the TCR, EOMG patients had elevated anti-Vbeta5.1 Ab's of the IgG class. This increase was restricted largely to EOMG cases with HLA-DR3 and with less severe disease, and it predicted clinical improvement in follow-up studies. EOMG patient sera containing anti-TCR Ab's bound specifically the native TCR on intact Vbeta5.1-expressing cells and specifically inhibited the proliferation and IFN-gamma production of purified Vbeta5.1-expressing cells to alloantigens in mixed lymphocyte reaction and the proliferation of a Vbeta5.1-expressing T cell clone to an AChR peptide, indicating a regulatory function for these Ab's. This evidence of spontaneously active anti-Vbeta5.1 Ab's in EOMG patients suggests dynamic protective immune regulation directed against the excess of pathogenic Vbeta5.1-expressing T cells. Though not sufficient to prevent a chronic, exacerbated autoimmune process, it might be boosted using a TCR peptide as vaccine. 相似文献
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The development of a quantitative ELISA for antibodies against human platelet antigen type 1a 总被引:1,自引:0,他引:1
BACKGROUND: Severe neonatal alloimmune thrombocytopenia is often due to antibodies against human platelet antigen type 1a (HPA-1a). The aim of this study was to develop a quantitative ELISA for the measurement of antibodies against HPA-1a. STUDY DESIGN AND METHODS: HPA-1a glycoprotein (GP) IIb-IIIa was immobilized and mixed with recalcified anti-HPA-1a-positive plasma overnight at 4 degrees C. The beads were washed, the antibodies against HPA-1a were eluted, and the eluate pH level was promptly adjusted. The purified antibodies were dialyzed and used for the development of an ELISA incorporating HPA-1a-coated plates. RESULTS: Serial doubling dilutions of the purified antibodies resulted in consistent sigmoid standard curves with a sensitivity of 0.5 microg per mL. To determine the reproducibility of the ELISA, antibodies against HPA-1a in five plasma samples (Samples A-E) were measured at serial doubling dilutions in four separate assays. Three of the samples (Samples A-C) contained antibodies against HPA-1a. The mean amounts in microg per mL (+/- SD, percentage of CV) obtained in the four assays were as follows: Sample A, 133 (9.4, 7.1%); Sample B, 16.5 (1.7, 10%); and Sample C, 8 (0.8, 10%). The amounts in the two antibody-negative controls (Samples D and E) were consistently less than 0.2 microg per mL. CONCLUSION: Using immobilized HPA-1a1a, antibodies against HPA-1a has been purified, and a quick and simple quantitative assay has been developed. 相似文献
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I N Pessah F C Mohr M Schiedt R M Joy 《The Journal of pharmacology and experimental therapeutics》1992,262(2):661-669
delta-Hexachlorocyclohexane (delta-HCH) is shown to be 30-fold more potent as a positive inotropic agent with rat atrial strips compared with lindane (gamma-HCH). Threshold and ED50 values for enhanced contractile force at a pacing frequency of 0.5 Hz are less than 1 microM and 2.2 microM for delta-HCH and 40 microM and 63 microM for gamma-HCH, respectively. Contracture developed in atria exposed to greater than 4 microM delta-HCH (ED50 = 11 microM) but not in atria exposed to gamma-HCH. Uptake and release of Ca++ measured from actively loaded cardiac sarcoplasmic reticulum (SR) vesicles is measured with antipyrylazo III. Although delta-HCH (30 microM) decreases Ca(++)-dependent ATPase by 20%, it does not significantly alter Ca++ loading in the presence of ruthenium red. Addition of delta-HCH (5-50 microM) after loading is complete causes rapid, dose-dependent release of Ca++ from SR. Ca++ release induced by delta-HCH is markedly stereoselective. Compared with gamma-HCH (50 microM), delta-HCH (50 microM) induces a nearly 20-fold higher initial rate of Ca++ release (4.3 nmol of Ca++/mg/sec). Studies with [3H]ryanodine demonstrate that delta-HCH sharply inhibits Ca(++)- or daunorubicin-activated radioligand binding (IC50 = 37 and 25 microM, respectively, logit slope = 2). Inhibition of [3H]ryanodine-binding by delta-HCH is stereoselective inasmuch as IC50 values for alpha, beta and gamma isomers are greater than 100 microM. The delta-HCH modified Ca++ channel appears to proceed by a noncompetitive mechanism (reducing Bmax in equilibrium experiments) with respect to the conformationally sensitive binding site for [3H]ryanodine.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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